PLATE XII. 



RIGHT HUMERUS OF TRICERATOPS PRORSUS MARSH. 



(See p. 60.) 

 Plate prepared under the direetion of Marsh. 



Specimen No. 4S42, U. S. National Museum. 

 Fig. 1. Anterior view. 

 Fig. 2. Proximal view. 

 Fig. 3. Distal view. 

 Fig. 4. Internal view. 

 Fig. 5. Section of shaft. 



One-fourth natural size. 



222 



